SPECTRAL SENSITIVITY, PHOTOPIGMENTS, AND COLOR-VISION IN THE GUINEA-PIG (CAVIA-PORCELLUS)

Behavioral discrimination tests and electroretinogram (ERG) flicker photometry were used to measure spectral sensitivity and to define the spectral mechanisms of the guinea pig (Cavia porcellus). Results from these 2 approaches converge to indicate that guinea pig retinas contain rods with peak sensitivity of about 494 nm and 2 classes of cone having peak sensitivities of about 429 nm and 529 nm. The presence of 2 classes of cones suggests a retinal basis for a color vision capacity. Behavioral tests of color vision were conducted that verified this prediction: Guinea pigs have dichromatic color vision with a spectral neutral point centered at about 480 nm. The cone pigment complement of the guinea pig is different from that known to characterize other rodents.